| Extrasolar planet | List of extrasolar planets | |
|---|---|---|
| Parent star | ||
| Star | HD 190984 | |
| Constellation | Pavo | |
| Right ascension | (α) | 20h 11m 30.7166s |
| Declination | (δ) | –64° 37′ 13.694″ |
| Apparent magnitude | (mV) | 8.76[1] |
| Distance | approx. 330[1] ly (approx. 100[1] pc) |
|
| Spectral type | F8V[1] | |
| Orbital elements | ||
| Semimajor axis | (a) | 5.5[1] ± 1.3 AU (820 ± 190 Gm) |
| ~55 mas | ||
| Periastron | (q) | 2.4 AU (350 Gm) |
| Apastron | (Q) | 8.6 AU (1280 Gm) |
| Eccentricity | (e) | 0.57 ± 0.10[1] |
| Orbital period | (P) | 4885 ± 1600[1] d (13.37 ± 4.4 y) |
| Orbital speed | (υ) | 12.2 km/s |
| Argument of periastron |
(ω) | 318 ± 5[1]° |
| Time of periastron | (T0) | 2,449,572 ± 1600[1] JD |
| Semi-amplitude | (K) | 48 ± 1[1] m/s |
| Physical characteristics | ||
| Minimum mass | (m sin i) | 3.1[1] MJ |
| Discovery information | ||
| Discovery date | October 19, 2009 | |
| Discoverer(s) | Santos et al. | |
| Detection method | radial velocity (HARPS) | |
| Discovery site | La Silla Observatory | |
| Discovery status | Preprint[1] | |
| Other designations | ||
|
HIP 99496 b
|
||
| Database references | ||
| Extrasolar Planets Encyclopaedia |
data | |
| SIMBAD | data | |
HD 190984 b (also known as HIP 99496 b) is an extrasolar planet which orbits the F-type main sequence star HD 190984, located approximately 330 light years away in the constellation Pavo. This planet is at least three times more massive than Jupiter and takes 13 years and four-and-a-half months to orbit the star at a semimajor axis of 5.5 AU with an eccentricity of 0.57.[1] This planet was detected by HARPS on October 19, 2009, together with 29 other planets.
Since this is a very long-period planet detected by the radial velocity method that this planet didn't complete the orbit during the continuous observations, the error range for orbital period is very large, at 4885 ± 1600 days or 13.37 ± 4.4 years. This puts it in the range of semimajor axes between 4.2 and 6.6 AU or between 630 and 990 Gm. So this planet will need couple more years of observations to better constrain the period and semimajor axis.